Some groups partially consumed by melting pots.
A very developed culture and society that would require vastly more military power than China has before they could be pacified. Hundreds of years ago it could have been done. Today not.
Kashmir, although split between two synthetic 'countries', is not at risk of disappearing nor surrendering. The Indian army is feeding itself into a meat grinder, which probably was partially planned by their own colonial masters An experiment as a synthetic country federalizes and tries to consume a more authentic nation.
Similar to the Uighers and Kashmiris, but with much more regional support. Israel, like India, is a recently created synthetic nation trying to control a more homogenous group. Militarily it could have been done in the distant past, today it is a path to ruin.
Indigenous Americans are far more diverse than any of the previous groups, and many of their number have gone extinct already, but they are also the most racially distinct of all the groups listed on this page, and would offer the most to humanity if they were to develop free from any "owner".
In the other direction, the least authentic original society, the purest 'colonizer', is the United States. The U.S. has no authentic roots of its own, it exists solely from the power it can scavenge from its victims. Because it has been doing this for hundreds of years it has acquired the appearance of authentic cultural existence and power.
Here is a generic path.
Step 1 / Realize that it benefits both sides
First the 'owner' society has to be clear on what it wants. Does it actually want to be try to own another group of people? Does it want to try to finish consuming it?
Those societies that continue trying to consume and absorb their 'pets' will grow weaker and weaker relative to those which encourage independence.
Step 2 / Physical Security
For any 'owner' society that chooses wisely, the next step is to make hard physical boundaries within which the former victim can develop as a rival. That would have been counterintuitive 500 years ago, would have led to ruin, but the day of the forced melting pot is past.
Step 3 / A core economy
Once the 'pet' society has secure physical boundaries with an historical basis the next step is to not interfere with the development of an economy in the former 'pet' society.
Step 4 / Shedding Colonial diseases, part 1
An important part of restoring tribal surviveability is discarding those tools that were used to conquer it in the first place. Among Naive Americans this includes Christianity.
Christianity was started long ago as a clever way to coerce a captive group into obedience and subservience.
As a belief system, it is a hodgepodge of values that are a mix of common sense and traditions from other religions, built around a supposed messiah, Jesus, who never actually existed. Historians are generally pretty clear that 'Jesus' was not an actual person. There is no record of his existence from the time he was supposedly alive, and many early mentions of him are by 'historians' who were being used to manage certain populations, historians whose specialty was a grey area between fact and fiction.
People who have been indoctrinated into a cult like Christianity often are very difficult to reason with. No matter what facts you present, they will find a fiction that, in their mind, beats it. And when they run out of fictions to defend their cult, they use weapons. The weaker their cult's basis is, the stronger their weapons need to be to defend it, and thus Europe, polluted long ago by the fictional cult of Jesus, has been converting masses at gunpoint for hundreds of years.
Step 5 / Step 6